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Based on the performance of various basic tests of this substance, Ning Chen quickly realized that these properties were very different from the predictions in Ning Chen's previous model.

But no matter what, it is a good achievement to be able to synthesize this new type of "potassium-iron-selenium" iron-based substance for the first time.

Next, Ning Chen told Xu Zhou about this result, and Xu Zhou looked very excited after hearing it.

"Ning Chen, how did you synthesize this substance?"

The molecular formula of this substance is K2Fe4Se5. Xu Zhou knew that this was a substance that had never been artificially synthesized before in the materials world.

Putting aside the various properties of this substance, just successfully synthesizing this new substance is enough to publish an SCI.

"Actually, the method is very simple, that is, mix various high-purity raw materials together in a certain proportion, and then sinter them in a solid phase."

This method is the so-called "sintering method", which is a very common method in the field of material synthesis.

Of course, this method seems really simple, but in actual operation, there are many details.

For example, how to proportion the starting raw materials, how to control the degree of grinding of the raw materials, how much the temperature and pressure during the sintering process should be controlled, etc.

If one of the details is not mastered, it will ultimately be difficult to synthesize the ideal substance.

Ning Chen also experienced hundreds of failures before gradually figuring out some successful techniques and methods.

Xu Zhou carefully checked Ning Chen's measurement data of this new material, and frowned inadvertently.

"Ning Chen, are you going to prepare to measure the superconducting properties of this material next?" Xu Zhou asked.

Because the superconducting critical temperature of superconductors is very low, the measurement of superconductors often requires the use of refrigerants such as liquid helium and liquid nitrogen.

Compared with the measurement of other properties, the measurement of superconducting properties is much more complicated.

"Teacher Xu, this material is most likely not a superconductor."

Ning Chen was very calm when he said this, as if he already knew the result.

Seeing Ning Chen say this, Xu Zhou also nodded and said:

"Well, I think so too. Judging from the properties currently measured, the probability that this material is a superconductor is indeed very low."

In fact, Xu Zhou had just come to this conclusion just because Ning Chen had just completed the synthesis of this substance, and Xu Zhou didn't want to pour cold water on Ning Chen.

But seeing that Ning Chen himself was aware of this problem, Xu Zhou no longer had so many worries.

"Teacher Xu, based on the properties of the material we have now obtained, we can determine that there is a vacancy for every five iron atomic positions, and this vacancy exists in the center of the other four iron atoms. From this, we can calculate Out of its composite magnetic moment..."

As Ning Chen spoke, he wrote the entire calculation process on the scratch paper.

"Finally, we calculated that its energy gap is about 300meV. From this, we can judge that this material is an insulator. Even near absolute zero, there is a high probability that it does not have superconducting properties."

Although in theory, insulators may have superconducting properties under some special circumstances, this possibility is slim.

Ning Chen and Xu Zhou came to this conclusion because this material was different from the model that Ning Chen had constructed before that might have superconducting properties.

"It doesn't matter, Ning Chen. Regardless of whether this material is a superconductor or not, if you can combine it, it is already very powerful. And I suggest you test it again, just in case you can detect any unexpected properties. ?”

"Well, Teacher Xu, I will definitely take a test." Ning Chen nodded.

Ning Chen did not really expect that such an extremely unlikely event would occur, but continuing to complete these measurements would ensure the integrity of the entire experimental process.

In the following time, Ning Chen came to the measurement center and completed the measurement of the superconducting properties of this material.

Unsurprisingly, the material did not exhibit any superconducting properties at low temperatures.

To be more precise, it is even an antiferromagnetic insulator, completely contrary to the properties of a superconductor.

After returning, Ning Chen told Xu Zhou the measurement results, and Xu Zhou made some new discoveries.

"Not bad! This special magnetic structure is very unique. What do you think, do you want to consider writing a paper based on this result? Maybe you can publish a second area, or even a first area!"

If Ning Chen had been so encouraged by Xu Zhou before, he might have stopped experimenting and started writing a thesis.

After all, the results of one area and two areas are considered a good result for most researchers.

However, after having the experience of publishing one article in Nature, three articles in the Journal of the American Mathematical Society, and receiving the Simons Scholar Award, Ning Chen's vision also quietly changed.

"Mr. Xu, don't rush to write the paper. I'll see how far I can go with this topic first, and then I will decide how to write the paper and whether to develop it separately."

Blindly splitting the results may affect the value of the entire result.

In addition, Ning Chen's experimental topic is superconducting and superconducting materials. If he finally publishes a paper on magnetic structure, Ning Chen himself will feel dumbfounded.

After experiencing this setback, Ning Chen did not continue the experiment immediately. Instead, he analyzed all the experimental data and experimental phenomena obtained so far, and carefully analyzed the reasons.

After thinking about it carefully, Ning Chen also figured out the problem.

"The reason why no superconductor has been synthesized is because of the iron atom vacancy here. It seems that I still have a big problem with the element ratio."

In previous experiments, due to a large number of failures in substance synthesis, Ning Chen was eager to successfully synthesize a new iron-based system of substances.

This allowed Ning Chen to gradually begin to adjust the ratio of elements based on experimental phenomena instead of adjusting based on the previously established model.

"If you want to truly synthesize a superconductor, you still need to fill the vacancy of this iron atom."

To achieve this goal, the method sounds very simple, which is to increase the proportion of iron.

Of course, in actual operation, there are too many problems involved.

…

After improving the material model, Ning Chen readjusted the ratio of each element and continued his experiments.

The next experiment still did not go so smoothly, but Ning Chen was mentally prepared. Even if it failed hundreds or thousands of times in the future, Ning Chen would firmly continue to explore forward.

Time has entered May unknowingly, and the graduation season is approaching, and the graduation defense of Shengzhou University undergraduates is about to begin.

Because of his special status, Ning Chen did not participate in the previous graduation project, thesis defense, mid-term defense, etc., but he still had to participate in the final formal defense.

After all, this is the last step to get the undergraduate degree certificate and graduation certificate. Ning Chen still attaches great importance to the defense, so he temporarily stopped the experiments in his hands and made various preparations before the defense.

This time, Ning Chen needed to participate in the defense of mathematics and materials at the same time. Of course, Ning Chen had many achievements in these two fields, but when choosing which achievement to use for the defense, Ning Chen still hesitated for a while.

"Hey, let's just use the Sine-Gordon equation in mathematics. If we come up with the three papers that prove Qiu Chengtong's conjecture, it would be a bit overkill."

After all, it is just an undergraduate graduation defense. If you directly take out the paper from the "Journal of the American Mathematical Society", I guess the review teacher may not know what questions to ask.

As for the defense of materials major, Ning Chen thought about it and did not choose the paper he published in "Nature".

Just presenting my research results on porous nano-silica particles is enough to successfully complete my graduation defense.

In the following time, Ning Chen completed the defense PPT of the two results and conducted a rehearsal of the defense process.

After all, there is a time limit for the defense. The time cannot be too short or too long.

If Ning Chen goes up to speak directly without any preparation, although Ning Chen can speak very well, if he accidentally fails to control the time, it will be difficult for the review teacher to do the grading work.

At the end of May, the undergraduate graduation defense began.

Ning Chen first participated in the defense of mathematics major.

Ning Chen, a sophomore undergraduate, came to the classroom with a group of seniors and seniors to prepare for the defense.

Although Ning Chen is the youngest in the entire classroom, no one would think that Ning Chen is really their junior.